The present invention relates to the field of cables used in building for participating in the structure of certain civil engineering constructions.
It is aimed more particularly at arrangements of such cables which give them good properties in the event of an earthquake.
The invention is especially applicable to the stay cables used for suspending portions of the construction, such as bridge decks. In a current embodiment, such a stay cable comprises a bundle of parallel reinforcements extending between two anchoring zones, one arranged on a pylon of the construction and the other on the suspended part. In the anchoring zone, the individual reinforcements of the stay cable have a slight divergence, so that they can be locked individually.
When a stayed construction experiences an earthquake, the suspended part, for example the bridge deck, undergoes abrupt and potentially considerable displacements with respect to the pylons. This results in high variations in traction and in flexion in the stay cables.
The flexural stresses are reflected in the anchoring zones and risk damaging the reinforcements and/or the anchoring devices.
The document WO 00/75453 describes an anchoring device for a structure cable, such as a stay cable, provided with guide means comprising an individual guide duct for each reinforcement, this duct widening in the direction of the running part of the cable, so as to allow an angular deviation of the reinforcement. The advantage of this anchoring device is that it ensures a progressive take-up of the flexural forces attributable to the convergence of the reinforcements toward the running part or of some transverse actions experienced by the stay cable. However, this force take-up may prove insufficient in the presence of the violent stress variations undergone in the event of an earthquake.